The invention relates to a weapon tube for firing spin-stabilized projectiles with driving bands, wherein the weapon tube has rifling in the form of grooves helically cut over the total periphery into a tube inside wall, so that a rifling groove flank forms on both sides toward a rifling groove bottom and thus encloses a respective rifling groove flank angle, and that lands exist between the rifling grooves so as to together determine a rifling profile for the tube. The projectiles for weapon tubes rifled in this way have one or sometimes even several driving bands (rotating bands), arranged one after another, for transmitting the spin, which driving bands are subjected to high stress during the firing acceleration inside the tube and are subjected to more or less high wear .
In order to raise the muzzle velocity and increase the range of an artillery weapon, the weapon tube is frequently lengthened, e.g. from 39 caliber lengths to 52 caliber lengths. As a result, the driving bands of the projectiles are stressed to their limits and wear out faster. The driving band wear can be reduced by reducing the surface pressure at the rifling groove flanks, whereby either the rifling angle (spin angle) is reduced or the number/depth of the rifling grooves or the driving band width are increased, or through a combination of these options. The surface pressure is caused by a rifling force R during the spin acceleration. Accordingly, the highest occurring rifling force must be used as a starting point for dimensioning the rifling grooves and driving bands.
The German published Patent Application No. DE-40 01 130 A1 describes a weapon tube with optimized rifling to improve the internal and external ballistics of the projectiles fired from this tube and to reduce driving band wear. The spin is optimized by taking into account a rifling force R(x), wherein the rifling angle is dissected into a Fourier series.
The German published Patent Application No. DE-42 00 171 A1 furthermore discloses a standardizing of the rifling force R(x) and teaches to use this to determine the rifling angle and also reduce the driving band wear. With the aid of this standardized rifling force and a predetermined final rifling angle, all relevant weapon tube parameters can already be specified during the production.
The rifling angle can be changed only slightly or not at all. Such a change jeopardizes the compatibility of some inserted projectiles. A change in the rifling depth, meaning the depth of a helical groove cut into the tube inside wall, jeopardizes the compatibility of all inserted projectiles. Changing the driving band width is not possible for inserted projectiles. To be sure, the use of more resistant materials for driving bands (e.g., soft iron instead of brass) leads to a reduction in the wear, but is highly problematic and rather involved, especially with inserted live projectiles (combat ammunition). In addition, it is to be expected that the service life of the weapon tube is negatively influenced.
It is the object of the invention to provide a weapon tube where the driving band wear at the projectile is reduced, without negatively influencing the projectile velocity in the muzzle region.